Telematics devices facilitate connecting a vehicle with a communications network. A telematics control unit (“TCU”) installed in a vehicle typically comprises a global positioning satellite (“GPS”) circuit, or module, wireless communication circuitry, including long range wireless (e.g., cellular telephony and data services) and short range wireless (“Bluetooth”) capabilities. A TCU typically includes at least one processor that controls, operates, and manages the circuitry and software running thereon, and also facilitates interfacing with a vehicle data bus.
For example, a TCU installed by a vehicle's original equipment manufacturer (“OEM”) such as Ford, Toyota, BMW, Mercedes Benz, etc., typically couples directly to the corresponding vehicle's data bus, such as, for example, a controller area network (“CAN”) bus, an international standards organization (“ISO”) bus, a Society of Automotive Engineers (“SAE”) bus, etc. The TCU can process and communicate information retrieved from the bus via links of the wireless communication networks, to a user's mobile device local to the vehicle, or a computer device remote from the vehicle. An OEM typically cautiously guards access by third party software to a vehicle's bus through a TCU because of the potential of computer virus infection, other malware, and software and data that although innocuous may nonetheless interfere with operation of the vehicle, which could expose the OEM to warranty liability and other liability.
Aftermarket vendors have begun packaging some components of a TCU in a module that plugs into a diagnostic connection of a vehicle, such as, for example, and OBD, or OBD-II port. Those of ordinary skill in the art typically refer to such a self-contained device as a ‘dongle.’ In addition, aftermarket vendors have also begun marketing a rear-view-mirror that includes some components of a TCU. A dongle typically receives power from the battery voltage power pin of the diagnostic port. The aftermarket rear view mirrors typically receive power through a wire, and trained technicians typically install the TCU mirrors.